Critical severity · published May 21, 2025
CVE-2025-34027
Versa Concerto Authentication Bypass File Write Remote Code Execution
9.0
CVSS
46.4%
EPSS
No
On KEV
Description
The Versa Concerto SD-WAN orchestration platform is vulnerable to an authentication bypass in the Traefik reverse proxy configuration, allowing at attacker to access administrative endpoints. The Spack upload endpoint can be leveraged for a Time-of-Check to Time-of-Use (TOCTOU) write in combination with a race condition to achieve remote code execution via path loading manipulation, allowing an unauthenticated actor to achieve remote code execution (RCE).This issue is known to affect Concerto from 12.1.2 through 12.2.0. Additional versions may be vulnerable.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)46.4% · higher than 99% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
Concerto · Versa
12.1.2 through 12.2.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-34027
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-34027
Exploit
https://projectdiscovery.io/blog/versa-concerto-authentication-bypass-rce
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8.8
CVE-2025-34025
Versa Concerto Insecure Docker Mount Container Escape
